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https://issues.apache.org/jira/browse/CASSANDRA-10254?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14729120#comment-14729120
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Sylvain Lebresne commented on CASSANDRA-10254:
----------------------------------------------
That's not a 2.1/2.2 error, it's a 3.0 backward compatibility issue. Basically,
3.0 changes a bit what it stores in the paging state (it uses only the
clustering while 2.1/2.2 have a full "cell name"), and while the code was made
so 3.0 node can read paging state from pre-3.0 nodes, the reverse isn't true
and that is a problem for mixed-version clusters.
So we need to allow 3.0 node to generate backward compatibles paging state. The
thing is however that while that is doable, it's also somewhat inefficient to
do so for 3.0 nodes, so while we should generate such backward compatibille
paging state, we should also have an upgrade path so that once your full
cluster is on 3.0, you don't have to bother anymore.
And the most viable way to do that I can think is to say that paging state are
native protocol dependent and a given state shouldn't been use between protocol
version. In other words, we'll maintain the backward compatible paging states
for the native protocol v3, but on v4 we'll use the current more simple and
efficient version. That does mean a driver that simultaneously connect to nodes
with different protocol version will have to careful with this, but 1) it
sounds reasonably fair and 2) at least the java drivers (and I'm sure other
drivers) doesn't support talking simultaneously to node with different protocol
version so that's not a problem.
> 3.0 paging states are incompatible with pre-3.0 nodes
> -----------------------------------------------------
>
> Key: CASSANDRA-10254
> URL: https://issues.apache.org/jira/browse/CASSANDRA-10254
> Project: Cassandra
> Issue Type: Bug
> Reporter: Blake Eggleston
> Fix For: 3.0.0 rc1
>
>
> When running the upgrade dtest {{TestCQL.static_columns_with_distinct_test}},
> the client appears to be passing in an invalid paging state (no cell name).
> Instead of catching the problem in validation and returning an error to the
> client, the select statement tries to run it, causing this exception:
> {noformat}
> ERROR QueryMessage.java:135 - Unexpected error during query
> java.lang.ClassCastException:
> org.apache.cassandra.db.composites.Composites$EmptyComposite cannot be cast
> to org.apache.cassandra.db.composites.CellName
> at
> org.apache.cassandra.service.pager.SliceQueryPager.<init>(SliceQueryPager.java:64)
> ~[main/:na]
> at
> org.apache.cassandra.service.pager.MultiPartitionPager.makePager(MultiPartitionPager.java:93)
> ~[main/:na]
> at
> org.apache.cassandra.service.pager.MultiPartitionPager.<init>(MultiPartitionPager.java:75)
> ~[main/:na]
> at
> org.apache.cassandra.service.pager.QueryPagers.pager(QueryPagers.java:102)
> ~[main/:na]
> at
> org.apache.cassandra.service.pager.QueryPagers.pager(QueryPagers.java:126)
> ~[main/:na]
> at
> org.apache.cassandra.cql3.statements.SelectStatement.execute(SelectStatement.java:228)
> ~[main/:na]
> at
> org.apache.cassandra.cql3.statements.SelectStatement.execute(SelectStatement.java:67)
> ~[main/:na]
> at
> org.apache.cassandra.cql3.QueryProcessor.processStatement(QueryProcessor.java:238)
> ~[main/:na]
> at
> org.apache.cassandra.cql3.QueryProcessor.process(QueryProcessor.java:260)
> ~[main/:na]
> at
> org.apache.cassandra.transport.messages.QueryMessage.execute(QueryMessage.java:122)
> ~[main/:na]
> at
> org.apache.cassandra.transport.Message$Dispatcher.channelRead0(Message.java:439)
> [main/:na]
> at
> org.apache.cassandra.transport.Message$Dispatcher.channelRead0(Message.java:335)
> [main/:na]
> at
> io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:105)
> [netty-all-4.0.23.Final.jar:4.0.23.Final]
> at
> io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:333)
> [netty-all-4.0.23.Final.jar:4.0.23.Final]
> at
> io.netty.channel.AbstractChannelHandlerContext.access$700(AbstractChannelHandlerContext.java:32)
> [netty-all-4.0.23.Final.jar:4.0.23.Final]
> at
> io.netty.channel.AbstractChannelHandlerContext$8.run(AbstractChannelHandlerContext.java:324)
> [netty-all-4.0.23.Final.jar:4.0.23.Final]
> at
> java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
> [na:1.8.0_40]
> at
> org.apache.cassandra.concurrent.AbstractTracingAwareExecutorService$FutureTask.run(AbstractTracingAwareExecutorService.java:164)
> [main/:na]
> at org.apache.cassandra.concurrent.SEPWorker.run(SEPWorker.java:105)
> [main/:na]
> at java.lang.Thread.run(Thread.java:745) [na:1.8.0_40]
> {noformat}
> Running {code} UPGRADE_MODE=none nosetests
> upgrade_tests/cql_tests.py:TestCQL.static_columns_with_distinct_test{code}
> should cause the error.
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